1. Field of the Invention
The present invention relates generally to recycling of cathode-ray tubes (xe2x80x9cCRTsxe2x80x9d), and more particularly, to an apparatus and method for rotating CRT panels to facilitate inspecting the seal edges of the panels.
2. Description of the Related Art
In recent years, there has been an increased demand for recycling of natural resources and prevention of environmental destruction. To meet this demand, studies and efforts have been made to reuse CRTs of used television sets and computer monitors.
A CRT, used as an image receiver incorporated in a television set, computer monitor, and the like, is a glass structure composed of a panel portion (also called a face portion) and a funnel portion (also called a panel skirt portion). The panel portion is made from a substantially transparent glass material for improving light transmittance, and the funnel portion is made from a glass material in which lead is mixed for preventing leakage of X-rays caused by collision of electron beams accelerated at a high voltage with a substance. The funnel portion and the panel portion are welded in a shield fashion to each other with frit glass (solder glass) into a tube shape.
Outwardly, an electron gun, a deflection yoke and the like are mounted on the external rear side of a CRT, and a shadow mask (or aperture grill) is provided in the CRT. A fluorescent screen provided on the inner surface side of the panel portion is normally coated with phosphors of three colors (red, green and blue).
Methods of recycling CRTs have been disclosed, for example, in U.S. Pat. Nos. 5,752,868 and 6,089,937. In these known methods, the CRTs are separated into a panel portion and a funnel portion, and the separate components are cleaned, inspected and recycled to make another CRT.
When the panel portion is separated from the funnel portion, the panel portion is cleaned and the seal edge is then inspected. The weight of CRT panel portions for large CRTs (e.g., 32 to 36 inch diagonal) is typically between 60 to 100 pounds, and therefore, suction cup lifts are required to pick up the panel portion and place it on a designated inspection surface. The suction cups can only pick the panel portion up by its face and place it with the seal edge down. Therefore, to inspect the seal edge, the panel portion must be rotated, preferably without picking the panel up physically by hand. An apparatus for holding and rotating the panel portions to facilitate this inspection process is needed.
It is an object of the present invention to provide an apparatus and method for holding and rotating CRT panels to facilitate inspecting the seal edges of the panels during CRT recycling.
It is a further object of the present invention to provide an apparatus for holding and rotating CRT panels which is economical to manufacture, efficient in use, capable of a long operating life, and particularly well adapted for use in inspecting seal edges of CRT panels during recycling processes.
According to the present invention, an apparatus for holding and rotating CRT panels is provided to facilitate inspecting a seal edge of the CRT panels during recycling. The apparatus includes a base frame and a support structure rotatably connected to the base frame for rotation about a horizontal axis. The CRT panel is placed into the support structure with the downward facing seal edge of the CRT panel positioned in a holding groove formed on an inner side of a bottom door assembly. A top door assembly is slidable to a closed position to enclose and support the CRT panel. The support structure is then rotatable approximately 180 degrees until the seal edge of the CRT panel is facing upward. The bottom door assembly is rotatable to an open position to allow inspection of the upward protruding seal edge of the CRT panel.
The top door assembly of the support structure is arranged to engage the base frame and prevent rotation of the support structure when the top door assembly is slid to its open position. The bottom door assembly is arranged to engage the base frame and prevent rotation of the support structure when the bottom door assembly is rotated to its open position.
According to a broad aspect of the present invention, an apparatus for holding and rotating CRT panels is provided, comprising a base frame and a support structure rotatably connected to the base frame for rotation about a generally horizontal axis. The support structure has a first side and a second side and a generally open construction between the first and second sides. The support structure has a first door assembly movable between a first position in which at least a portion of the first side is covered by the first door assembly, and a second position in which the first side is substantially open. The support structure also has a second door assembly movable between a first position in which the second side is substantially open for receiving a CRT panel portion, and a second position in which at least a portion of the second side is covered by the second door assembly.
According to another broad aspect of the present invention, an apparatus is provided for rotating heavy objects to facilitate inspecting a bottom side thereof. The apparatus comprises a base frame and a support structure rotatably connected to the base frame for rotation about a generally horizontal axis. The support structure has a first viewing side, a second receiving side, and a receptacle defined between the first and second sides. A first door assembly comprises at least one door rotatably mounted to the support structure to selectively open and close the first viewing side of the support structure. The first door assembly is arranged to engage the base frame and prevent rotation of the support structure when the first viewing side is open. A second door assembly comprises at least one door slidably mounted to the support structure to selectively open and close the second receiving side of the support structure. The second door assembly is arranged to engage the base frame and prevent rotation of the support structure when the second receiving side is open
According to still another broad aspect of the present invention, a method of rotating and inspecting CRT panels is provided, comprising the steps of: separating a CRT into a funnel portion and a panel portion; providing a rotatable support structure having a closed first side and an open second side; placing the panel portion into the support structure through the open second side; closing the open second side of the support structure to form an enclosure surrounding the panel portion; rotating the support structure approximately 180 degrees; opening the second side of the support structure; and inspecting a seal edge of the CRT panel protruding through the open second side of the support structure
Numerous other objects of the present invention will be apparent to those skilled in this art from the following description wherein there is shown and described an embodiment of the present invention, simply by way of illustration of one of the modes best suited to carry out the invention. As will be realized, the invention is capable of other different embodiments, and its several details are capable of modification in various obvious aspects without departing from the invention. Accordingly, the drawings and description should be regarded as illustrative in nature and not restrictive.